Mixed surfactant systems, used in many formulations, have aroused great attention and interest from researchers and industry due to the possibility of synergism. Alkyl polyglycoside (APG) and didecyldimethylammonium chloride (DDAC) mixtures combine the excellent properties of pure surfactants and play an important role in the development of multi‐functional washing products. To study the synergism between APG and DDAC, the physicochemical properties of different mixed systems have been investigated. The critical micelle concentration (CMC) is about 180 mg·L−1 and the surface tension at the CMC is about 26.0 mN·m−1 at a mass fraction of 40 % DDAC (ωDDAC40 %). The values are significantly lower than pure surfactants. The foaming property shows the best performance at ωDDAC20 %. When the mass fraction of DDAC is 80 %, the mixture exhibits better wetting and emulsifying properties. Synergism was observed in surface tension, foaming and emulsifying properties, while the wetting ability and detergency exhibited no such effects. Phase behavior of the APG/DDAC/water ternary system has also been carried out by polarized optical microscope. The phase diagram is characterized by a micellar phase, a region where lamellar and micellar phases coexist and a lamellar phase.

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A series of disodium alkyl monoglucoside citric monoesters (AG‐EC) were synthesized with an indirect method using glucosides, lauryl/decyl/octyl alcohol and citric acid. The structure and composition of the synthesized surfactants were defined by Fourier transform infrared spectroscopy (FTIR) and liquid chromatography–mass spectrometry (LC/MS). The surface properties, foaming ability and wetting ability were investigated. AG‐EC surfactants exhibited excellent water solubility which eliminated the defect of long‐chain alkyl glucoside. All three surfactants showed high surface activities. AG12‐EC and AG10‐EC showed remarkable foaming abilities in distilled water and hard water. Aqueous solutions of AG‐EC surfactants spread slowly on a parafilm surface.

A new method of synthesizing disodium alkyl polyglucoside citrate surfactant has been reported in the paper, in which citric acid anhydride was firstly prepared, and then reacted with alkyl polyglucoside to obtain ester. The structures of products were indicated by infrared spectroscopy. Moreover, the surface activities of raw materials and their corresponding products were investigated. The results show that products exhibit low surface tension in 28 mN/m. Comparing with raw materials, the disodium alkyl polyglucoside citrate surfactants possess better emulsification stabilities to oil acid, good foam abilities and excellent hard water-resistant properties.